Bisphenol A or BPA is an organic synthetic compound that belongs to the group of endocrine disruptors. It can be found in many plastic products such as food packaging, cans, dental sealants, children's toys, beverage containers and thermal paper. BPA can affect the endocrine, immune and cardiovascular systems by binding to various hormone and other receptors. In some products, it has been replaced by its substitutes, which have a similar chemical structure, physico-chemical properties, mechanisms and toxic effects. The aim of this master's thesis was to review and compare the effects of BPA and its substitutes on the immune system. The data for the systematic literature review were extracted from two databases: PubMed and ScienceDirect. We used the PRISMA methodology to select articles and studies that were relevant to our topic and research question. We found that most studies of the impact on the immune system were done for BPA and its analogues bisphenol S (BPS), bisphenol F (BPF) and bisphenol AF (BPAF), and therefore compared the results of their studies with each other. BPA and analogues had the greatest impact on human peripheral blood mononuclear cells (PBMC), which include T lymphocytes, B lymphocytes, monocytes, natural killer cells and dendritic cells. Increases in reactive oxygen species, hydroxyl radicals and lipid peroxidation have been associated with decreased cell proliferation and survival. Bisphenols influenced the ratio of pro-inflammatory to anti-inflammatory cytokines through various signalling pathways and transcription factors, in most cases promoting the development of inflammation in the body and slowing down the arrival of immune cells at the site of inflammation. In the last part of the master's thesis, we focused on the critical immunotoxicological effects of BPA, which led the EFSA's CEP Panel to lower the provisional TDI for BPA from 4 µg/kg/day to the currently valid TDI of 0.2 ng/kg/day. In our research, we found an association between exposure to BPA during pregnancy or early childhood and the development of allergic asthma with wheezing. Critical effects identified were also an increase in the number of specific IgE in allergic lung inflammation and an increase in the number of Th17 cells. The greatest inhibitory effect on the immune system was found with the substitutes BPF and BPAF, while BPS acts more as an activator of the immune system and causes hypersensitivity and allergic reactions. In the future, various new BPA alternatives are likely to replace the use of bisphenols in products. One such alternative is Pergafast 201, which is already used in the production of thermal paper, but more research on its toxicity and safe use in everyday life is needed.
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